The Gifted follows the Strucker family. The high school-aged son and daughter, Lauren and Andy, are both mutants. Lauren can push air and water molecules together, while Andy has some sort of vague but powerful telekinesis. Their dad Reed, however, works for a shadowy government agency that arrests mutants and places them in weird bags for storage. We see Polaris — a familiar mutant to comic readers — trapped in such a way, though it would seem she escapes at some point.
Once Reed learns that his children are mutants, he switches sides, and the entire Strucker family goes on the run and attempts to team up with an underground mutant network. It’s still unclear exactly how The Gifted fits into the X-Men timeline. One mutant, Eclipse, mentions that nobody is sure if the X-Men or Brotherhood even exist anymore.
So, it seems that The Gifted is going to be kind of like Logan, in that it takes place after the downfall of mutants, though it seems unlikely that the show will take place after Logan. Also, we see Blink, a teleporting mutant who also appeared in Days of Future Past, which further muddles any connections. Chances are The Gifted will be more like Legion in that it’s in the X-Men universe but not really that attached to any known continuity.
The Gifted doesn’t have an exact release date yet, but expect it sometime in late 2017.